JPS6211817A - Lens holding device - Google Patents

Abstract

PURPOSE:To simplify an assembly, and to prevent an optical axis from being shifted due to temperature and humidity, by holding a lens in a lens detaining part of an inside diameter part of a lens frame end part and a lens supporting member consisting of an elastic body of the lens frame end part. CONSTITUTION:A stopper 14 is provided on the inside peripheral surface of the end part of a lens frame 11, and a lens supporting member 13 consisting of an elastic body is provided as one body with the lens frame 11 so as to be connected to the stopper 14. An end face 12 of a lens 10 consisting of glass or plastic forms a taper, and the lens 10 is held by the elastic supporting member 13 and the stopper 4. As for the stopper 14 and the elastic supporting member 13, plural pieces (the figure shows a case of four pieces) are provided on the inside peripheral surface of the lens frame. When assembling the lens 10 is pushed in from the right side of the figure, and when the largest diameter part of the lens gets over the stopper 14, the elastic supporting member 13 is engaged to a tapered part 12, and the lens 10 is fixed. In such a way, the assembly is simplified, and a shift of an optical axis, which is caused by the variation of temperature and humidity is prevented.

Description

[Detailed Description of the Invention] [Field of Industrial Application] The present invention relates to a lens holding device, and in particular, it is easy to attach the lens to the lens frame, and it also prevents deformation of the lens due to changes in lens diameter, thickness, or other factors. The objective of the present invention is to provide a lens holding device that can elastically absorb the lens and correct misalignment, inclination, etc. when the lens is held in the lens frame, and can always hold the lens in the correct position with respect to the lens frame. It is something to do.

[Conventional technology]

Conventionally, as shown in FIG. 1, as a holding device for a lens frame, a lens fitting part 5 is provided on the inner periphery of a lens frame 1, and includes a stepped part 6 for abutting the lens 2. A threaded portion 4 is screwed onto the front inner periphery of the joint portion 5 to constitute a lens holding portion on the lens frame 1.

Then, after fitting the outer peripheral part 2a of the lens 2 inserted from the opening side of the lens frame 1 with its back side in contact with the stepped part 6 side, the outer peripheral part 2a of the lens 2 is inserted into the lens holding part of the lens frame 1. Screw the presser ring 3 onto the threaded portion 4, and use the presser ring 3 to hold the lens 2.
There is one in which the back surface of the outer circumferential portion 2a is pressed against and fixed to the stepped portion 6. Furthermore, when fixing the final lens of the lens system to the end of the lens frame, there is a method in which the end of the lens frame is bent and the lens is fixed by caulking.

[Problem that the invention seeks to solve]

According to the former conventional lens holding device, there is a tolerance value in terms of processing accuracy for the lens fitting part 5 in the lens holding part of the lens frame 1 and the lens 2 itself, and the tolerance value between the two exists. Under the condition where play occurs, misalignment occurs by the above-mentioned tolerance value.

Moreover, when the lens 2 is a plastic lens, the above-mentioned tolerance must be set even larger due to dimensional changes due to temperature or variations between lenses during molding.

Incidentally, the allowable values for a lens with a diameter of 20 m are as shown in Table 1 below, and it is clear that the maximum misalignment in the case of a plastic lens is 0.05 inches.

Table 1 In addition, in the conventional lens holding device described above, when tightening the lens 2 by screwing the presser ring 6 into the threaded portion 4 of the lens frame 1, it is difficult to adjust the force to a constant level and the shape of the lens changes. This method has disadvantages in that it cannot absorb the deformation caused by the lens 2, which prevents the occurrence of misalignment of the lens, and furthermore, it takes time and effort to attach the lens 2 to the mirror frame 1.

Moreover, as a lens holding device,
Although the devices described in Publication No. 4 or Japanese Utility Model Application Publication No. 55-57709 have been proposed, no measures have been taken against misalignment or tilting of the lens, and no other consideration has been taken to overcome the above-mentioned drawbacks. It is something that has not been done yet.

In particular, the latter lens holding device does not have a structure for absorbing changes in outer diameter due to temperature and humidity when using plastic ivy lenses, and as a lens holding mechanism, there are problems with accuracy due to the above-mentioned points. The problem remains.

[Means to solve the problem]

Therefore, the present invention was developed in view of the above-mentioned conventional lens holding device, and specifically, the present invention includes a lens locking portion provided at the inner diameter of the end of the lens frame, and an elastic member formed at the end of the lens frame. It is characterized in that the lens is held by the lens support portion.

〔Example〕

Embodiments of the lens holding device according to the present invention will be described below with reference to the drawings.

Reference numeral 10 denotes a lens as a held lens held within the lens frame 11, and the outer periphery 10a of this lens 10 has a tapered surface 12 that is inclined in one direction.

Reference numeral 13 denotes an elastic piece as an elastic part that protrudes inward from the inner wall surface 11a of the lens frame 11. At the protruding root end 13a of each elastic piece 13, there is a stopper 14 for regulating the lens 10 in the optical axis direction. It is integrally formed with a protrusion.

Further, regarding the protruding direction of each elastic piece 13, the above-mentioned lens 1
The drawings show a case in which four elastic pieces 13 are arranged between the lens frame 11 in the inner circumferential direction so as to correspond to the inclination angle of the tapered surface 12 of 0. The number of pieces 13 is also not limited to integral molding, as will be explained for each embodiment below.

Further, the outer diameter of the lens 10 and the inner diameter between the elastic pieces 13 are set and configured so that the lens 10 can be elastically held by each elastic piece 13, and the inner diameter between the stoppers 14 of each elastic piece 13 is set and configured. In contrast, the maximum diameter of the lens 10 is configured to be large.

The lens 10 may be made of plastic or glass, and the lens frame 11 may be made of synthetic resin such as polycarbonate.

In order to hold the lens 10 in the lens frame 11 having the above structure, the lens 10 is inserted from the right side of the lens frame 11 in FIG.
When the lens 10 is forcibly inserted, the maximum outer diameter portion of the lens 10 hits the stopper 14 and pushes the opposing elastic pieces 13 outward, and when the maximum outer diameter portion of the lens 10 exceeds the stopper 14, the lens 10 closes. 10 itself is each elastic piece 13
When the return elasticity of each elastic piece 13 works, the lens 1
Each elastic piece 13 comes into pressure contact with the tapered surface 12 of the lens 10, and the maximum outer diameter part of the lens 10 is locked to the striker 14,
The lens 10 is held in a lens frame 11 while being fixed in a predetermined position by each elastic piece 13 .

Next, how the lens 10 is always held in the correct position by each elastic piece 13 will be explained with reference to FIG. 3.4.

When attaching the lens 10, when the lens 10 is inserted between the elastic pieces 13 in the lens frame 11, the lens 10
As shown in Figure 3, if the position is shifted and the cent is placed,
Regarding the inclination, if we consider the moment around the point a with the point a as the fulcrum, the force that the lens 10 receives from the elastic piece 13 when it is focused is as indicated by the arrow B.

The direction B is perpendicular to the plane of the elastic piece 13. If the direction of this force is to the right of line segments a and b as shown in FIG. 3, the lens 10 will be corrected in the correct direction by this force.

However, if the direction of this force is to the left of line segments a and b in FIG. 3, the lens 10 will be further tilted.
It can be said that when setting it up for the first time, there is no intentional tilting.

In addition, as for the deviation in the axial direction, as shown in Fig. 4,
When the position in the axial direction is shifted, the elastic piece 13 is attached to the lens 10.
The force becomes as shown by arrows c and c'.

Therefore, if this force is divided into an axial component and a radial component, it becomes as shown by the arrow D', E, and E', and D and D' act as forces to elastically hold the lens 10, while E ,
E' acts without moving the lens 10 in the axial direction, and the lens 10 moves until it is stopped at the bar 14.

As is clear from the above description, the lens 10 includes each elastic piece 1.
The lens 10 can always be held at the originally expected correct position by the force to correct the inclination and the force to move the lens 10 in the axial direction and press it against the stopper in step 3. In the case of a plastic lens, Compared to conventional lens holding devices, the center misalignment can be suppressed to about one-third.

Now, instead of the first embodiment of the lens holding device of the present invention, the second to 18th embodiments will be described below with reference to FIGS. 5 to 21.

The second embodiment shown in FIG.
b is bent outward to provide a guide end 15, so that the lens 10 can be mounted while being inserted from either the front or rear direction of the elastic piece 13.

In the third embodiment shown in FIG. 6, the stopper 16 is formed by an inner step of the lens frame 11, and a guide end 17a is provided at the tip.
The elastic piece 17 is formed of a metal or plastic lens separately from the lens frame 11, and the rear end 17b of the elastic piece 17 is inserted into the wall surface of the lens frame 11 and fixed. Since it is constructed by the wall surface of the lens frame 11 separately from the elastic piece, as in the first embodiment, the elastic piece 1
It is possible to expect the effect that the position of the lens 10 in the thrust direction can be accurately regulated without deforming together with the lens 3.

In the case of the fourth embodiment shown in FIG.
An elastic piece 20 having tapered surfaces 18 and 19 inclined in the direction and having a guide end 20a is attached to the lens frame 1 as in the third embodiment.
By inserting and attaching the stopper 22 into the wall surface of the lens 10 and having a tapered surface 22a on the stepped portion 21 of the lens frame 11, the elastic piece 20 and the stopper 22 can engage the tapered surface 18, 19 of the lens 10. An engaging recess is formed, and one tapered surface 18 is connected to an elastic piece 20.
The lens 10 can be held while the other tapered surface 19 is brought into contact with and locked to the tapered surface 2.28 of the stopper 22, and is suitable for application to a concave lens. In addition, the elastic piece 20
The tapered surface of the lens 10 formed by the stopper 22 and the engaging recess of 8°19 can further improve the centering accuracy in the lens holding state.

The fifth embodiment shown in FIG.
Instead of forming the stopper 16 integrally with the stepped portion of the wall surface of 1, an annular stopper 23 is formed separately from the lens frame 11 and is engaged with the engaging edge 24 of the wall surface, and is screwed into the wall surface. Screw the presser ring 26 onto the threaded portion 25 provided,
The stopper 23 is fixed, and an elastic piece 27 having the same structure as the elastic piece 17 in the third embodiment is oriented in the opposite direction to that in the third embodiment, and the rear end 27b is inserted into the wall surface and fixed. It is constructed by

The tip 27a of the elastic piece 27 presses against the tapered surface 12 provided along the outer periphery of the lens 10, and the stopper 2
3 holds the lens 10 within the lens frame 1 by pressing firmly.

The sixth embodiment shown in FIG. The tapered surface 18.1 of the lens 10 is connected to the tip 27a of the piece 27 and the tapered surface 23a provided on the stopper 23.
9 constitutes an engaging recess for receiving, and the holding state is the same as in the fourth embodiment. Incidentally, since the configuration is based on the fifth embodiment, the same numbers as in the fifth embodiment are used for illustration.

In the seventh embodiment shown in FIG. 10, the stopper 23 in the fifth embodiment is screwed into the threaded portion 29 of the lens frame 11 using an annular protrusion 28 that projects integrally from the wall surface of the lens frame 11. The structure of holding the lens 10 is the same as that of the fifth embodiment.

The eighth embodiment shown in Figure 11 is a holding device in which the outer periphery of the lens 10 is provided with tapered surfaces 18, 19 that are inclined in two directions, and a pair of elastic pieces 3], , 32 are opposed to each other to hold the lens frame 1.
By fixing with a presser ring 35.36 screwed onto the threaded part 33.34 of 1, the tip 31a of the elastic piece 31.32,
The structure of the stopper is adjusted by the engagement recess formed by 32a, and is configured to be able to elastically engage and hold the tapered surfaces 18 and 19 of the lens 10.

The ninth embodiment shown in FIG. 12 shows a configuration in which a pair of elastic pieces 37 and 38 are fixed at the same time by - number of presser rings 40 by interposing a spacer 39 between them.
In the case where the holding device is provided with a tapered surface 1.8.19 that slopes in two directions at 0, the four engaging parts by a pair of elastic pieces 37 and 38 have one end 37a and the other middle side 38.
It consists of a. 41 indicates a threaded portion.

In the tenth embodiment shown in FIG. 13, the stopper of the first embodiment is constructed by an engagement recess 43 of the elastic side 42 and a retaining protrusion 44 protruding from the tapered surface 12 of the lens 10, so that they engage with each other. It is designed to be held by forcing it. Incidentally, it is also possible to configure the engaging recess and the protrusion in opposite directions, and such a configuration is specifically shown in the first embodiment shown in FIG. 14. In the figure, 45 is an engagement protrusion of the elastic side 42;
Reference numeral 46 designates four engaging parts provided on the tapered surface 12 of the lens 10.

15th to 18th, 20.21 12th to 15th degrees 17.
In each of the 18 embodiments, the inner wall surface 11a of the lens frame 11 and the lens 1
This shows a configuration in which the lens 10 is held elastically by interposing an elastic member 47 between the tapered surfaces 12 provided on the outer periphery of the lens 10.

In the twelfth embodiment, one tapered surface 19 of the lens 10 is fixed by a stopper 48, and the lens 10 is held by an elastic member 47 interposed between the other tapered surface 18 and the inner wall surface 112 of the lens frame 11. The elastic member 47 is engaged with the inner wall surface 11a by an engagement protrusion 49.

In the thirteenth embodiment, the stopper 48 is not provided, and the V-shaped tapered surface 18, 19 of the lens 10 and the inner wall surface 11 of the lens frame 11 are
8, the elastic member 47 is held by a protrusion 50 on the inner wall surface 11a.

In the fourteenth embodiment, a lens 52 having a tapered surface 51 having an arcuate cross section is held by interposing an elastic member 47 having an elastic piece 53 that curves in accordance with the shape of the tapered surface 51.

The 15th embodiment is an example in which the lens 10 is held at the open end of the lens frame 11. One tapered surface 19 of the lens 10 is fixed to the tapered surface 54 of the open end, and a support is provided that protrudes from the open end. By attaching the elastic member 47 to the arm 55, the elastic piece 56 presses and holds the other tapered surface 18.

In the 17th embodiment, one surface of the outer periphery of the lens 10 is locked to a stepped portion 57 of the lens frame 11, and an elastic piece 58 of an elastic member 47 interposed between the tapered surface 12 and the inner wall surface 11a of the lens frame 11 is used. While pressing against the tapered surface 12, the tip 58 of the elastic piece 58
A protrusion 59 protruding from the lens 10 is engaged with the outer peripheral edge of the lens 10 to prevent the lens 10 from moving in the axial direction.
is maintained.

In the 18th embodiment, a support member 63 is provided with a stopper 60 and an elastic piece 61 on one side, and an elastic support arm 62 on the other side.
is interposed between each of the large number of lenses 10 and between the inner wall surface 118 of the lens frame 11, so that each lens 10 can be connected to the stopper 6.
0, the elastic piece 61 presses the tapered surface 12 of the lens 10, and the other support arm 62 supports the adjacent front lens 10 while holding a large number of lenses 10 in an arrayed state. It is configured to do this.

In the 16th embodiment shown in FIG. 19, an elastic piece 64 integrally extended from the open end of the lens frame 11 holds down one of the tapered surfaces 18 and 19 inclined in two directions. 65 while the other tapered surface 19 is fixed and held.

〔Effect of the invention〕

The lens holding device of the present invention has the above configuration,
It simplifies the work of attaching the lens to the lens frame, and when it is attached, it is held in place by the elasticity of the elastic part, eliminating the need for torque adjustment when tightening conventional screws. Because the lens is held elastically through the taper,
temperature.

Lens diameter caused by humidity and other factors.

Changes in thickness can be absorbed by the elasticity of the elastic portion, and the occurrence of misalignment or inclination can be prevented.

[Brief explanation of drawings]

Fig. 1 is a sectional view of a conventional lens holding device, Fig. 2a is a side sectional view of the first embodiment of the lens holding device of the present invention, Fig. 2 is a longitudinal sectional front view of the same, and Figs. 3 and 4 are elastic FIGS. 5 to 21 are side sectional views, with some parts omitted, showing the second to 18th embodiments. ■, 11... Lens frame 2.10.52... Lens 3... Holding ring 4... Screw part 5... Lens fitting part 6... Step part 12.18, 19.51 ...lens tapered surface 13
．． 17, 20.27, 31°32.37. 38.42° 56.58, 61.64... Elastic piece 14.16, 22, 23, 28° 48.60... Stopper 15... Guide end 21... Step part 24... Engagement Joint edge 25.29.33, 34.41...Threaded part 26.30
, 35, 36, 40... Presser ring 39... Spacer 43, 46... Engagement recess 44, . 45...Engaging protrusion 47...Elastic member 49.50...Engaging protrusion 53...Elastic piece 54...Tapered surface 55...Support arm 57...Step part 59... Projection 62...Support arm 63...Support member

Claims (1)

[Claims] (1) A lens locking portion provided on the inner diameter of the end of the lens frame, and a lens locking portion provided integrally or integrally with the end of the lens frame that resiliently presses and holds the outer periphery of the lens engaged with the locking portion. 1. A lens holding device comprising: a lens supporting portion; and a lens is supported so as to be held between the locking portion and the supporting portion.